When most of us hear the word fermentation we typically think of food products like yoghurt or wine, but the latest research shows this ancient method of food preservation is also effective when it comes to achieving nourished, glowing and healthy skin. The process of fermentation is a transformation process, and in fact, it’s one you might already be familiar with without realizing how commonly it is used in the cosmetics industry. For example, the popular skincare ingredient lactic acid, is produced after a process involving fermenting milk. The list is constantly growing with new ingredients that have been developed and concentrated via the fermentation process.  There are many more ingredients already shown to be beneficial for the skin, that are becoming popular due to the new characteristics that have been gained after fermentation, including soy, ginseng, radish root, yacón root and many more.

Skincare containing fermented ingredients can supercharge a skincare routine through the action of enhanced antioxidant support and the greater bioavailability of key bioactive compounds to improve the overall condition and health of the skin and prevent many inflammatory skin conditions.

What Is Fermentation?

The process of fermentation is one in which microorganisms like bacteria and yeast digest and break down or alter an ingredient and transform the chemical structure into a new form or compound. This results in the generation of new skin-friendly ingredients like probiotics and acids like lactic and acetic. Probiotics benefit the skin’s overall health by supplying nutrition to feed the microbiome, the ecosystem of bacteria that lives on the skin and modulates the immune system.  Lactic acid is an alpha-hydroxy acid that is known to be one of the gentlest chemical exfoliants for people with sensitive skin, assists in holding water in the skin and helps the skin turnover and removal of dead skin cells. The type of fermentation and the microorganisms used will have an impact on the many different metabolites (also known as postbiotics) that are produced as an end product of the fermentation. These postbiotics are rich in nutrients, vitamins, amino acids, organic acids, polysaccharides, and beta-glucans that nourish the skin and regulate the immune system.

How Do Fermented Ingredients Benefit The Skin?

There are a number of benefits that result from fermentation, but the most important are the balancing of the microbiome, the creation of new ingredients, increased potency of ingredients, increased penetration of ingredients into the skin, and increased preservation of the final skincare product.

1. Fermented Ingredients Balance the Microbiome

The greatest benefit obtained from fermentation is the production of probiotics. Fermented skincare works by balancing the levels of good and bad bacteria on your skin.  Many of the residents of the skin microbiome are essential to maintaining healthy skin. When the skin’s microbiome becomes unbalanced, pathogenic bacteria can flourish and cause good bacteria to reduce in numbers. This can cause issues such as dermatitis, eczema, sensitivity, and acne.

Fermented skincare products can help restore the equilibrium of the microbiome by increasing the number of good bacteria, which have a selective advantage over the disease-causing species. When your skin’s microbiome is balanced, enzymatic reactions can function optimally, allowing it to more effectively produce natural humectants. These draw moisture into the skin to keep it hydrated, making it appear plump and glowing. Probiotics may also help in improving your skin barrier function, and have been shown to reduce the inflammatory reactions present in skin disorders.

2. Fermentation Creates New Skincare Ingredients

Fermentation creates molecules like peptides, lactic acid and hyaluronic acid, and can enhance the production of ceramides, the lipids that form the skin’s barrier and help skin retain moisture.  They also help to stimulate the production of skin's natural antimicrobial peptides, helping to regulate pathogenic or acne causing bacterial levels.

3. Fermentation Increases the Concentration of Bioactive Compounds

Many studies have shown that skincare ingredients become more powerful after fermentation, which can lead to increased skincare benefits and more noticeable results. This translates into greater antiaging benefits for the skin. Any ingredient that is already good for the skin will be amplified after the fermentation process.

4. Fermentation Increases the Bioavailability of Ingredients

The increased penetration of ingredients that have been fermented is due to the fact that fermentation breaks down ingredients into smaller parts. Due to the chemical reactions undergone during the fermentation process, the key ingredients found in fermented skincare tend to be of a smaller molecular size, so they may be able to be more readily absorbed by the skin, this is often referred to as making the ingredients ‘biocompatible’ or ‘bioavailable,’ a process that also assists with increased potency.  This process also enhances the antioxidant potential of raw ingredients and encourages the growth of the probiotics living on the surface of the skin, helping to maintain homeostasis.

5. Fermentation Increases the Shelf life of a Product

Finally, fermentation can actually increase a product’s shelf life as many of the byproducts of fermentation are naturally antibacterial and antifungal. Depending on the type of fermentation used, metabolites like organic acids, including lactic acid and acetic acid create a low pH environment, an evolutionary step utilized by commensal microorganisms to prevent the growth of pathogenic bacteria, allowing the skincare product to last longer with a smaller amount of preservatives needed for the preservation of the end product.

What Does the Research Say?

There are numerous studies providing evidence of the benefits of specific probiotic strains for skin health [1,2,3]. In addition, the mechanisms of anti-ageing suggest strains can help to regulate pH, reduce oxidative stress, protect from photoaging, and improve the skin barrier function [4].

A ferment of Saccharomyces demonstrated anti-inflammatory properties in vivo, which could be due to its function as a prebiotic to modulate and promote probiotic strains present on our skin to produce essential fatty acids [5,6].

Lactobacilli and Bifidobacterium are the most commonly used probiotics are thought to mediate skin inflammation, treat atopic dermatitis and prevent allergic contact dermatitis. Probiotics are shown to decolonize skin pathogens (P. aeruginosa, S. aureus, A. Vulgaris, etc.) through the production of antimicrobial byproducts and prebiotics and support the immunity of the skin. Finally, prebiotics (e.g. Alpha-Glucan Oligosaccharides) can contribute to the treatment of diseases including allergic contact dermatitis, acne and photoaging primarily by enhancing the growth of probiotics [7].

A 2012 study by the Department of Food and Nutrition at Korea University found that fermented red ginseng had greater concentrations of antioxidants than non-fermented, and "increased anti-wrinkle and pigmentation reducing efficacy"[8].

Who Would Benefit From Fermented Skincare?

The good news is that the answer is almost everyone, as products that use high-quality fermented ingredients are safe for even the most sensitive skin. Fermented products are commonly used for their anti-inflammatory and skin-calming benefits, making them especially useful for those with inflammatory skin conditions like eczema, dermatitis, rosacea or acne. 

References:

1. Navarro-López V., Martínez-Andrés A., Ramírez-Boscá A., Ruzafa-Costas B., Núñez-Delegido E., Carrión-Gutiérrez M.A., Prieto-Merino D., Codoñer-Cortés F., Ramón-Vidal D., Genovés-Martínez S., et al. Efficacy and safety of oral administration of a mixture of probiotic strains in patients with psoriasis: A randomized controlled clinical trial. Acta Derm. Venereol. 2019;99:1078–1084. doi: 10.2340/00015555-3305. 
2. Yu Y., Dunaway S., Champer J., Kim J., Alikhan A. Changing our microbiome: Probiotics in dermatology. Br. J. Dermatol. 2020;182:39–46. doi: 10.1111/bjd.18659. 
3. Korpela K., Salonen A., Vepsäläinen O., Suomalainen M., Kolmeder C., Varjosalo M., Miettinen S., Kukkonen K., Savilahti E., Kuitunen M., et al. Probiotic supplementation restores normal microbiota composition and function in antibiotic-treated and in caesarian-born infants. Microbiome. 2018;6:182. doi: 10.1186/s40168-018-0567-4. 
4. Sharma D., Kober M.M., Bowe W.P. Anti-aging effects of probiotics. J. Drugs Dermatol. 2016;15:9–12.
5. Jensen GS, Carter SG, Reeves SG, Robinson LE, Benson KF. Anti-inflammatory properties of a dried fermentate in vitro and in vivo. J Med Food. 2015;18(3):378-384. doi:10.1089/jmf.2013.0158
6. Evans M, Reeves S, Robinson LE. A dried yeast fermentate prevents and reduces inflammation in two separate experimental immune models. Evidence-based Complement Altern Med. 2012;2012. doi:10.1155/2012/973041
7. Lolou V, Panayiotidis MI. Functional Role of Probiotics and Prebiotics on Skin Health and Disease. Fermentation. 2019; 5(2):41.
8. Lee HS, Kim MR, Park Y, et al. Fermenting red ginseng enhances its safety and efficacy as a novel skin care anti-aging ingredient: in vitro and animal study. J Med Food. 2012;15(11):1015-1023. doi:10.1089/jmf.2012.2187